FEATURE ARTICLE 2: MENTAL HEALTH
An individual's ability to relate with their family, friends, work-mates and the broader community is affected by their mental health. People suffering from a mental disorder can experience significant distress and disability.

The annual cost of mental illness in Australia has been estimated at $20 billion, which includes the cost of lost productivity and labour force participation. In 2003, mental disorders were identified as the leading cause of healthy years of life lost due to disability.

This article focuses on people aged 16-85 years who had experienced mental illness or substance use disorder in the 12 months prior to being surveyed in 2007.

Definitions

Unless otherwise stated, the information in this article relates to people aged 16-85 years and is based on the International Classification of Diseases and Related Health Problems (ICD-10). Some ICD-10 disorder criteria have a 'diagnostic exclusion rule', so that one disorder takes precedence over another. This means that if, for example, a person's symptoms of anxiety are due to the presence of post-traumatic stress disorder, that person will not also be diagnosed with generalised anxiety disorder.

All prevalence data presented (including comorbidity data) are subject to diagnostic exclusion rules. While this article often separates the discussion of mental disorders by type, some of the people interviewed had more than one mental disorder which may add to the effects and/or severity they experience.

Data source

Most of the information in this article comes from the 2007 National Survey of Mental Health and Wellbeing (SMHWB). Measuring the prevalence of mental disorders in the community is a complex task, as such disorders are usually determined through clinical diagnosis. The SMHWB only covered those disorders which could be identified using an interview-based household survey. A modified version of the Composite International Diagnostic Interview was used to diagnose disorders.

The SMHWB was also conducted in 1997 but there were differences in the application of the diagnostic criteria in 1997 compared with 2007, so the results are not comparable and 1997 data are not shown in this article.

PREVALENCE

In 2007, 45% of Australians aged 16-85 years, (or 7.3 million people), had at some point in their lifetime experienced a mental disorder. In the 12 months prior to the survey women were more likely than men to have had symptoms of mental illness. A higher rate of anxiety disorders among women was the main contributor to this difference (graph 11.17).

Anxiety disorders generally involve feelings of tension, distress or nervousness. In 2007, anxiety disorders were the most common class of mental disorders, affecting 14% of all people aged 16-85 years in the 12 months prior to the survey. Women were more likely to have experienced anxiety disorders than men, 18% to 11% (graph 11.18). Anxiety disorders were most common in women aged 16-54 years, (21%), compared with women aged 65-85 years (6.3%).

Affective disorders

Affective or mood disorders involve mood disturbance or change in affect. Depression and dysthymia may involve signs such as a depressed mood, loss of self-confidence and esteem and reduced energy or activity over a period of at least two weeks. Bipolar disorder involves episodes of mania either alone or together with depressive episodes. Manic episodes may be characterised by less need for sleep, increased activity or restlessness and reckless behaviour. Affective disorders affected 6.2% of people aged 16-85 years, 7.1% of women and 5.3% of men. The rate was higher for those aged 16-44 years (7.6%) than for those aged 55-85 years (3.3%) (graph 11.18).

Substance use disorders

Substance use disorders, involving harmful use of, or dependency on, alcohol or other drugs were slightly less prevalent than other types of mental disorders, affecting 5.1% of people aged 16-85 years. Substance use disorders were more common in men than in women and most prevalent in men aged 16-24 years (13%) (graph 11.18).

11.18 Proportion of people with a mental disorder in the^ previous 12 months - 2007

Severity

A range of criteria, such as suicide attempts, substance dependence and interference in various areas of a person's life, are combined to obtain a measure of the overall level of impairment experienced by people with mental disorders. The impairment is categorised into three levels: severe, moderate and mild. Higher levels of severity may be associated with a range of factors, in particular, affective disorders and comorbidity. Of all people with a mental disorder in 2007, just over one-fifth (21%) had a severe disorder, one-third (33%) had a moderate disorder and just under half (46%) had a mild disorder.

Comorbidity

People with a mental illness may have more than one disorder at any one time. This is known as comorbidity. The disorders may or may not be from the same group of mental health disorders. Having multiple mental disorders is associated with greater impairment, higher risk of suicidal behaviour and greater use of health services.

In 2007, 1.4 million or 38% of people with a disorder had two or more 12-month mental disorders. A mix of affective and anxiety disorders was the most common combination.

Employment provides income as well as an opportunity for social engagement and improved self-esteem. In 2007, unemployment was higher for those with a mental illness (4.0%) than those without (2.7%). The employment to population ratio was lower for people with a mental illness (69%) than those without (76%). The gap was greater for women than men (8 percentage points compared with 3 percentage points).

MENTAL HEALTH SERVICE USE

Recent decades have seen less use of residential mental institutions and increased use of community mental health services. People with a mental illness may use a variety of services to help improve their ability to work or care for themselves.

In 2007, nearly two-thirds (65%) of people with a mental disorder had not used services for their mental health problems in the 12 months before the survey. Most of those people who did not access any services reported that they had no need for any type of assistance.

People aged 16-34 years were less likely to have used services for their mental health problems (29%) than people aged 35-54 (41%) or 55-85 years (37%) (table 11.19). The most common group of disorders for young people was substance use disorders (often related to alcohol). These were more likely to be mild disorders and may have therefore contributed to the lower rate of service use.

Women (41%) were more likely than men (28%) to have used services for mental health problems. This is consistent with higher usage of health services by women in general.

Of people with an affective disorder, 50% reported using services for mental health problems, compared with less than a quarter of people with an anxiety disorder or 11% of those with a substance use disorder. This may be related to the differing severity levels of these types of disorders, since over half of those people with an affective disorder were rated as severe.

11.19 People with mental disorders(a), by health services used for mental health problems(b) - 2007

General practitioner

Psychologist

Other(c)

Total who used services for mental health problems

People who had a need not fully met

%

%

%

%

%

Sex

Male

18.0

13.1

15.1

27.5

25.2

Female

29.9

13.2

19.9

40.7

28.9

Age group (years)

16-34

20.3

11.8

14.7

28.6

26.2

35-54

27.7

16.2

21.0

40.5

30.3

55-85

28.9

8.7

17.6

37.3

22.1

Geography

Major Cities of Australia

25.5

15.5

18.6

36.9

29.4

Other areas of Australia

22.9

8.3

16.0

30.8

22.7

Mental disorders

Mood disorder only

41.9

*21.0

23.0

49.7

33.5

Anxiety disorder only

12.2

6.5

10.4

22.0

15.8

Substance-use disorder only

*6.9

**4.5

*5.6

*11.1

7.2

One mental disorder only

15.8

8.4

11.3

24.0

16.7

Two or more mental disorders

39.3

21.0

28.3

52.7

44.6

Total aged 16-85 years

24.7

13.2

17.8

34.9

27.3

* estimate has a relative standard error of 25% to 50% and should be used with caution

** estimate has a relative standard error greater than 50% and is considered too unreliable for general use

(a) People aged 16-85 years with mental disorders within the previous 12 months

(c) Other health professional includes: medical specialists, other professionals providing general services and complementary and alternative therapists.

Source: ABS data available on request, National Survey of Mental Health and Wellbeing.

The most common service used was visiting a GP (25%), followed by seeing a psychologist (13%) (table 11.19). GP consultation was the most common service used by both sexes, across all ages, types of mental disorders and across geographical areas.

Men and women with mental disorders were equally likely to use the services of a psychologist for mental health problems however people from major cities were almost twice as likely to have used a psychologist (15%) compared with those from other areas (8%). This may be related to less access to such services outside major cities.

In 2007, there were about 872,000 people who had a mental health disorder and felt they had an unmet need for assistance. The most common type of perceived unmet need was for counselling (16%), followed by information (14%) and social intervention (12%).

Mental health services in Australia

In the four years to 2007-08, expenditure on state and territory mental heath services as a whole increased by an average of 5.6% per year, to $3.0 billion.

The introduction of Medicare Benefits Schedule (MBS) allied health items for people with chronic conditions and complex care needs in July 2004, followed by the introduction of the MBS items provided by psychologists, occupational therapists and social workers from November 2006, resulted in the overall number of services subsidised by Medicare for both psychiatrists and allied health professionals to almost double to nearly 4 million in 2007-08, from just over 2 million services per annum in the three years prior to 2006-07.

The number of visits to GPs for mental health reasons increased by an average of 4.4% per year in the four years to 2007-08, to an estimated 11.9 million encounters that year.

Geographic differences were also evident in the MBS subsidised mental health services provided by psychiatrists and allied health professionals (psychologists, social workers and occupational therapists) in 2007-08. The age standardised rate per 1,000 mental health services per person was 12.3 in Major cities, 2.9 services per 1,000 people in Remote areas and 1.6 services per 1,000 people in Very remote areas.